What is this thing-a-ma-bob?

[Radarguy]

Hi guys,
I picked up a cigar box at a tool show for $5 full of interesting items like a working dial indicator, miscellaneous indicator holding devices, a 1x2x3 block, a couple of beam type parallels and this thing. Its the only thing in the box I could not identify. Can anyone? The top part looks like a radius gage but if it is how is it used. The machining is top notch.

 

[DAN_IN_MN]

How about a couple more pictures from different angles. What are the approximate dimensions of it?

Does the tail sticking out the left look like it was clamped in a tool post?

 

[Flammable_Solid]

Looks like part of an old vernier caliper to me.

 

[DAN_IN_MN]

Looks like part of an old vernier caliper to me.

And the part to the left would be the movable jaw.??

 

[Harvey Melvin Richards]

It looks to me like it came off of a vernier height gauge. The part sticking out is where the scribe would attach. Like the gauge in the back in this photo, except with a removable scribe like the one in front.

 

[lrsglory]

That is definitely a go. Off of a vernier height gage.

 

[awander]

Looks like it's the movable piece from a Starrett 454.


I could use the thumbscrew, if you don't want it.

 

[Radarguy]

You guys are tops! That is what it is. I had not noticed the shaft slots in the top part but that is exactly what it is. Just missing one screw and the ruler!
I will see if I have anything else to stump you guys with.
Thanks,
Russell